Frequencies Outside of the Human Hearing Range

17 Jul Frequencies Outside of the Human Hearing Range

My assigned project at Oregon Caves National Monument and Preserve is to process recordings from bat acoustic recording units and to upload the data to NaBat, which is the North American Bat Monitoring Program. First, I have to make sure that the recording units are working and recording properly. Once the recording units are known to be working well, they are ready for deployment near the cave entrance or exit, or anywhere within the preserve that is known to be a site for high bat activity. Afterwards, the recordings are processed using SonoBat, a software used to process bat calls and to classify the calls to the species level! So cool! The software is very accurate with the classifications, but I always have to make sure these are classified correctly using a bat call sheet provided by SonoBat. The software also provides bat call frequencies from all bat species found in North America so that these can be used to compared with the calls I have uploaded to the software. Once everything is processed, the data is uploaded to NaBat by following their protocols. The bat acoustic recording units can also be used for when field work begins. They can be placed around the preserve and can tell us where we there is high bat activity for mist netting. I cannot wait to start handling bats and continue to learn more and more about these amazing creatures!

Echolocation calls on a sonogram of my favorite bat, the hoary bat (Lasiurus cinereus) showing harmonics and variations in frequencies.

Testing acoustic recording units at cave exit before deployment